1. Field
The present invention relates to a backlight driving apparatus which drives a backlight unit used in a liquid crystal display device, and more particularly, to a backlight driving apparatus which drives a backlight unit with an AC power supply.
2. Discussion of the Background
Recently, flat panel display devices, due to their various utilizations, have been widely used not only in mobile devices, in which miniaturization and low power consumption are essential, but also large-size digital TVs for which the weight and thickness should be reduced. Among them, liquid crystal display devices have been the most widely used technology. Since a liquid crystal panel is not self-luminous, a liquid crystal display device requires a light source that is called a backlight unit (BLU) which is provided on a back surface of the liquid crystal panel.
Since light that is generated from a backlight unit passes through a liquid crystal layer and color filters to be shown from an outside, the backlight unit is a large factor in the performance of the LCD display device. For example, not only the picture quality of the liquid crystal display device, but also the weight, design, lifespan, and power consumption of the liquid crystal display device are greatly influenced by the backlight unit.
Since a backlight units currently used include a plurality of LEDs, the performance of the backlight unit is determined depending on a method for driving the LEDs.
A backlight unit that is used in a typical display device turns on LEDs with a driving method using a DC voltage. For this, an AC voltage that is supplied to the liquid crystal display device is converted into a DC voltage to thereby drive the LEDs, and a separate converter circuit should be additionally provided.